Conventionally, there have been known display devices having a touch panel that receives input operations. In such type of display devices, a pressed position on the touch panel can be detected by various systems, such as a pressure sensitive system that senses a pressure and reacts to it, and an electrostatic capacitance system that reacts to a change of an electrostatic capacitance between a finger and a conductive film.
Regarding such type of display devices, for example, there has been disclosed a pressure sensitive touch panel that calculates a pressed position based on a pressure value detected by a pressure sensor arranged at the four corners of a back face of the touch panel.
Japanese Patent Application Laid-open No. 2006-126997 is an example of documents related to the above conventional techniques.
However, in the conventional techniques, there has been a problem that, when a pressure sensitive touch panel is applied to a display device incorporated in a vehicle, the display device occasionally makes an erroneous detection such that a position different from a pressed position intended by an operator is detected as the pressed position.
Furthermore, in a pressure sensitive touch panel incorporated in a vehicle, there has been another problem that, even when an operator is not performing any pressing operation, an erroneous detection is made such that a pressing operation has been performed due to an effect of vibrations of the vehicle.
Due to the above problems, there has been an important issue as to how to realize a display device capable of preventing erroneous detections of a pressing operation caused by vibrations of a vehicle as well as erroneous detections of a pressed position.